Design of folded hybrid silicon carbide-lithium niobate waveguides for efficient second-harmonic generation

A design of a highly efficient second-harmonic generation hybrid silicon carbide (SiC)-thin-film LiNbO3 optical device is presented with a normalized nonlinear conversion efficiency as high as 1280%/(W-cm2). It is shown that low-loss bends and tapers in the SiC rib can be used to fold the device into any desirable aspect ratio to meet design requirements or fabrication limitations. Direct numerical integration of the coupled-wave equations is used to simulate the generated second-harmonic output power under a variety of fabrication tolerance considerations.